Effects of Si doping in high-quality AlN grown by MOVPE on trench-patterned template

The effects of Si doping on the structural properties of a high-quality AlN layer grown on a trench-patterned AlN/sapphire by metalorganic vapor phase epitaxy (MOVPE) were systematically studied. With a high Si doping concentration, void formation became much slower than that in undoped AlN film. This phenomenon was attributed to the anti-surfactant effect of Si in the growth process. Moreover, as the Si doping concentration increased, compressive stress was significantly relaxed in Si-doped AlN films. A high Si doping concentration of 1×1018 cm−3 was successfully achieved for AlN grown at 1500 °C.

► High-quality AlN layers were grown on a trench-patterned AlN/sapphire by MOVPE. ► With Si doping in AlN, the anti-surfactant effect was observed. ► With increasing CH3SiH3 flow rate, compressive stress was significantly relaxed in the AlN layer. ► Si doping with concentration of 1×1018 cm−3 was successfully achieved for AlN grown at 1500 °C.